ORIGIN OF GELATINE. 143 



actually occurs as one of the products of the trans- 

 formation of choleic acid, yield in both cases a for- 

 mula closely approaching to the composition of 

 gelatinous tissues. We must, however, attach to 

 such formulae, and to the considerations arising from 

 them, no more importance than justly belongs to 

 them. I would constantly remind the reader that 

 their use is to serve as points of connection, which 

 may enable us to acquire more accurate views as to 

 the production and decomposition of those com- 

 pounds which form the animal tissues. They are 

 the first attempts to discover the path which we 

 must follow in order to attain the object of our re- 

 searches ; and this object, the goal we strive to 

 reach, is, and must be, attainable. 



The experience of all those who have occupied 

 themselves with researches into natural phenomena 

 leads to this general result, that these phenomena 

 are caused, or produced, by means far more simple 

 than was previously supposed, or than we even 

 now imagine ; and it is precisely their simplicity 

 which should most powerfully excite our wonder 

 and admiration. 



Gelatinous tissue is formed from blood, from 

 compounds of proteine. It may be produced by 

 the addition, to the elements of proteine, of allan- 

 toine and water, or of water, urea, and uric acid ; 

 or by the separation from the elements of proteine 

 of a compound containing no nitrogen. The solu- 

 tion of such problems becomes less difficult, when 



